Heat-insulated receptacle.



W. STANLEY. HEAT TNSMVWD RFGEPTAULE.

APPMCMION :Pimm Ma, ww

gqnmmam 7, mmm agp-. 1913.

ATTORNEYS i sr onirica.

pecicatin ofv Letters latent.

patenten sept. 2 191s.

application tiledv August 5, 1&12. Serial No. 713,245.

To all whom it may concern Be it known that I, WrLLiAM STANLEY, acitizen of the United States, and a resident of Great Barrington,Berkshire county,

State of Massachusetts, have invented certain new and usefulyImprovements in Heat- Insulated Receptacleaof which the followin is aspecification.

y invention relates lto heat insulating barriers and more particularlyto the insulation of receptacles havlng an inner shellsurrounded by anouter shell with a vacuous space therebetween and commonly known asvacuum bottles etc. My invention, however, may be applied to milk cans`and many other devices and arrangements.

'.Ihe common vacuum receptacle has its shells or walls constructed ofglass and accordingly such receptacles are very liable to breakage andcannot withstand hard usage. Moreover, it is found that a very highdegree of exhaustion must be maintained in the vacuous space in order toget sufficient heat insulation to make the devices practicable forordinary uses. Further'- 4more, because such receptacles are made of`glass they are limited in size.

The main objects of my invention are toi overcome one or more of thesedifficultles or 4 i it 1s only necessary tofiexhaust the spaces,

disadvantages.

In lorder to produce bottles which are not liable to breakage it hasbeen suggested that the shells be constructed of metal instead of glassbut such bottles have been found entirely unsuccessful vbecause the highde-Q gree of exhaustion required is not maintamed 1n the vacuous space,probably because 'under the greatly reduced pressure the metal givesoft` .gas for a long time which reduces the degree of exhaustion tosuchan extent that the bottles have ,not

great enough insulating powers to render them usable for most purposes,so that they i are entirely impractlcable. In order to overcome thesedifficulties I fill the vacuous space with a finely divided materialwhich will not give ofl'l any material amount of gas to materiallychange the gaseous pressure in the exhausted space. If the space befilledwith such a material the same degree of heat insulation may beobtained at a much less reduced gaseous pressure e., much lessexhaustion) in the vacuous space, and the said much less reducedpressure will be maintained substantially constant even in a vesselconstructed with metallic shells,

probably because the metal does not give ofi" a sufficient amount of gasto materiallychange the reduced gaseous pressure in the vacuous space. Ipreferably, however, use

a finely divided substance which will not only not give ofi' gas in thevacuous s ace, but ,will 'have'in addition the power o absorbing anysmall amount of gas given ott' to the vacuous space by the metal shells.

I am' aware that it has been suggested that the vacuous space of areceptacle of the class in question be filled with a finely di videdsubstance, butin every -such case, as far as I am aware,the material hasbeen o-f a character to give ouf gas in the vacuous 'space so that intime the exhaustion and heat insulation powers became so reduced thatthe receptacles became practically inoperative and entirely unfit forthe pur-Y not give oft' any material amount of gas in` the vacuousspace.

As stated above, a high degree of exhaustion is required to insulate the(glass) vacuum bottle of commerce. In my bottle a much lower vacuum 1srequired, because voids, or cavities left in'the filling material (whichvoids or cavities are of a microscopic order of magnitude) to a' pointat which the average distance between all the molecules of the residual`gas is approximately equal to the diameter or distance across thevoids, high thermal insulation being thus obtained when the order ofmagn itu'de of the ressure of the residual gas is one hundred) haustedbottle of commerce. In other words, the introduction of roperly chosenfinely divided filling materia `may permit the exhaustion to be onehundred times less than is necessary if no such filling is used. A stillgreater exhaustion will increase to some .extent the insulation, but itis rarely necessary. The degree of exhaustion necessary to produce agiven insulation depends Lupen ythe -fneness of division of thematerial. It will, however, be clear that the use ofsuch a finelydivided substance, which will not give off gas or one which will absorbgas in the vacuous space, is of times as great as the re-4 sidualgaseous pressure 1n the common exspecial importance if the receptacle beconstructed with metallic shells.

Further objects, features and advantages will morel clearly appear fromthe detailed description given below taken in connection with theaccompanying drawing which forms a part of this specification. Thedrawing shows a vertical section of a vacuum bottle embodying myimprovements in one form. y

Referring to the drawing, 1 represents an inner steel cylindrical shellprovided with a top portion 2 welded thereto at 3. The body of thevshell 1 is cylindrical in shape. Extending symmetrically about the innershell is an outer metal cylindrical shell 4 having a bottom 5 securedthereto. The two shells are connected together entirely around the mouthof the receptacle by means of a steel neck 6 welded to the top 2 at f?,and secured to the outer shell t at 8, 'so as to form a space betweenthe two shells which may be suitably exhausted. The inner sury faces ofthe shell 1 with its top2 andl neck 6 are covered with any suitable orwell known vitreous or vitrified coating such as enamel, etc., or theymay be tinned or covered with a protecting varnish or the like, in orderthat the inside ofthe vessel may be protected and easily kept clean andsanitary.

Extending about the neck of the bottle is a circular piece 9 having itslower portion threaded at 10. For closing the mouth of the bottle astopper 11 of cork or other suitable material is inserted therein, andover this is placed a metallic cup-shaped cap 12 threaded at its lowerportion 13 for, engagement with the screw threads at 10. The' bottom 5is recessed at la'and provided with a metal tube 15 through which thespace between the shells may be exhausted (say to .O1-m. m.), and afterexhaustion the tube is crimped and soldered to effectively seal thevacuous space. A.V lower base or bottom 16 is secured to the outer shell4.- after exhaust-ion to complete the receptacle. outside surfaces ofthe receptacle may be nickeled and beads 16 and 17 provided in the shell4 to strengthen the receptacle. 'In order to more securely hold thelower end of the innerl shell 1 in place with respect to the outershell, I provide a spider lconnecting the two shells, which consistsprincipally of a projection 18 secured to the bottom of the inner shelland small links, wires or chains 19 connecting this projection with theouter shell 4. Thelinks,wires or chains 19 are of so high thermalresistance that their heat conducting power is negligible.

Before putting on the bottoms 5 and 16 the space between the shells isfilled with a finely powdered material 20 chosen or prepared so as notto give oft' any material amount of gas at ordinary temperatures atlnarily employed, as any The y which such receptacles are designed to beused. "For this purpose sublimed silica forms a good substance and maybe used with success. By filling the vacuous space with this material avery high degree of heat insulation may be obtained with a much lessreduction of gaseous pressure than ordismall amount of gas given oft" bythe metallic walls under theseconditions will not materially adect vthegaseous pressure and corresponding heat insulation.

Obviously other substances may be used to lill the vacuous space.Evenmaterials which are ordinarily good heat conductors if in sufhcientlfinely divided condition, may be used. guch substances as metallicoxids, finely divided metals, etc., may be used, the nature of thefilling substance being quite immaterial provided it is sufficientlydivided and will not give olf gases (including vapors) after theexhaustion.

If desired, a finely divided substance may be used which will not onlynot give off gas to the vacuous space but will have an appetite for gasor the power of absorbing gas under the conditions of use. A suitablematerial for this purpose is finely divided carbon which has been highlyheated to remove occluded gases and also heated inthe vacuous space atthe time of exhaustion to a temperature higher than the temperature atwhich the receptacle is to be generally used. The carbon so treated willthereafter absorb any small amounts of gas given oft' to the vacuousspace by or from the metallic shells and thus aid in keeping up the ex'-haustion necessary for proper insulation. The carbon will so act evenwhen hot materials are placed in the receptacle, since it is necessaryto heat the carbon nearly to the ytemperature at which it was heated atthe in order to produce the same degree of heat ,l

insulation I prefer to practically fill the vacuous space with thefinely divided substance. A certain amount of heat transmission throughthe sides and neck of a receptacle of the class described is usuallypermissible but by reducing the losses through the neck the same'insulation value of the re-4 ceptacle may be maintained with a greatergaseous pressure (less exhaustion) in the vacuous space whereby anysmall amountot' gas which may be given oli to the space by the metallicparts will not make such a liao great percentage of change in thegaseouspressure and the degree of insulation is more nearly maintainedconstant. In'order to reduce the losses lthrough the neck lto bringaboutthis result, I provide the receptacle with a long narrow 'neck 6'extending from the seam 7 to the top21. The neck though of metal, yetbeing long and narrow has such a'high thermalV resistance that .thelosses therethrough are small.` By increasing the v amount of exhaustionhowever, the high resistance feature of the neck may be omitted.Although I have described my invention with respect to certainparticular embodiments thereof, nevertheless Ido not desire to belimited to the particular details shown and described except as clearlyspecified in the appended claims, since many changes, modifications andsubstitutions may be made without departing from my invention in itsbroader aspects and my invention in its broader aspects may be founduseful 'in many other applications thereof.

Having fully and clearly described my invention, what I claim as new anddesire to secure by Letters Patent, is:

1. A heat insulating barrier comprising two metallic walls suitablyconnected and spaced apart,` the space between said walls being filledwith finely divided material which will absorb gas at'ordinarytemperatures and reduced pressures, the said space being exhausted tosuch a degree as to greatly reduce the conductivity for heat between thetwo metallic walls.

2. A heat insulated receptacle having an inner metallic shell with avitreous coating on its inner surface and an outer metallic shellextending about the inner shell and spaced therefrom and connected tothe inner shell at the mouth of the receptacle-by a metallic neck ofhigh thermal resistance, the space between said shells being filled withfinely divided material substantially incapable of giving off gas butwhich will absorb gas at ordinary temperatures and -reduced pressures,and the said space also being exhausted to such 'a degree as to greatlyreduce the conductivity for. heatlbetween the two shells.

A heat insulating barrier comprising two walls suitably connectedand'spaced apart to form a vacuous space therebetween, said spacecontaining finely divided material substantially incapable of givin offgas at ordinary temperatures and reduced pressures, and the said spacebeing exhausted to such a degree as to greatly reduce the conductivityfor heat between the two walls.

4. A heat insulated receptacle having an inner metallic shell and anouter metallic shell extending about the inner shell and spacedtherefrom and connected to the inner shell at the mouth of thereceptacle by `shell extending abouty the inner shell and spacedtherefrom andconnected to the inner shell at the n1oufh`of thereceptacle, the space between said shells being filled with finelydivided material incapableyof giving off gas at ordinary temperaturesand reduced pressures, and the said space also being exhausted to such adegree as to greatly reduce the conductivity for heat between the twoshells.

6. A heat insulated receptacle having an'inner shell, and an'outer shellextendl ing about the inner shell and spaced therefrom and connected tothe inner shell at the mouth of the receptacle, and the space betweensaid shells being filled with finely divided material which will absorbgas at ordinary temperatures and at the reduced pressures of the space,the said space also being exhausted to such a degree as to greatlyreduce the conductivity for heat between the two shells. i

7. A heat insulated receptacle having an inner shell, andan outermetallic shell extending about the inner shell and spaced therefrom and`connected tothe inner shell at ,the mouth of the receptacle by a neck ofhighthermal resistance, and thespace be tween said shells being filledwith finely divided material which will absorb gas at ordinarytemperatures andreduced pressures, and the said space also 'beingexhausted to such a degree as to greatly reduce the con ductivity forheat between the two shells.

8. A heat insulating barrier comprising `two walls,suitably connectedand space apart to forni a vacuous space therebetween, said space beingfilled with finely divided `material substantially incapable of givingofin gas at ordinary temperatures and reduced pressures, and the saidspace being exhausted to such a degree as to greatlyreduce theconductivity for heat between the 'two' walls.

9'. A'heat insulated receptacle having an inner metallic shell and anouter metallic shell extending about the inner shell and spacedtherefrom and connected. to the inner shell at the mouth thereof, thespace between said shells being exhausted add filled with a'finelydivided material which hasvbeen heated in the space atithe time ofexhaustion to a temperature higher than the ordinary temperatures atwhich the ieceptacle is to be generally used, whereby between saidshells containing finely divided material which has been heated in thespace f at the .time of exhaustion to a temperature higher than theordinary temperatures at which the' receptacle is to` be generally used,whereby the material is adapted to absorb gas from the space at ordinarytemperatures at which the receptacle is to be generally used, said spacebeing exhausted lto such a degree as to greatly reduce the conductivityfor heat between the two shells. l

' 11. A heat insulated receptacle having an interior metallic shell andan exterior mel tallic shell extending about the inner shell and spacedtherefrom and connected to the inner shell at the mouth of thereceptacle, the space between said shells contaii'iing finely dividedmaterial which has been heated to a temperature higherthan the ordinarytemperatures at which the recep tacle is to be generally used, wherebythe material is adapted to absorb gas from the space at ordinarytemperatures at which the receptacle is to be generally used, said spacebeing exhausted to such a de'Oree as to greatly reduce the conductivityfbor heat between the two shells.

12. A heat insulated receptacle comprising metallic walls, suitablyjoined, embracingf a vacuous Space lilled with finely di# vided materialwhich will not give olf gas to the space at ordinary temperatures, vsaidspacebeingexhaust-ed to such a degree to greatly reduce the conductivityfor heat across said space.

13. A heat insulated receptacle compris- .ing spaced metallic wallssuitably joined to Aform a vacuous space, said space being filled 'voidsor cavities.

14. A heat insulated receptacle compris ing spaced walls, suitablyjoined, -to form a vacuous space therebetween, said space being filled'with a finely divided lsubstance which will not give ol' gas in thevacuous space at ordinary temperatures and which leaves voids orcavities ofa microscopic orderv of magnitude and the number of which is'practically infinitely large, said voidsv or cavities being exhaustedof gas only to about such an extent as. to separate the molecules of gasby an average distance greater than the average distance across saidvoids or cavities.

15. A heat insulating barrier comprising two Walls suitably connectedand yspaced apart to formV a vacuous space therebetween, said spacecontaining finely divided mate# rial which will absorb gas at theordinary temperatures and reduced pressures, .the said space beingexhausted to .such a degree as to greatly reduce thefconductivty :forheat-between the two walls.

In testimony whereof, I have signed my name to this specification, inthe presence of 'two subscribing witnesses.

WILLAM STANLE Y.

Witnesses C. P. RANDOLPH, F. 1G. LARAMEE.

